{"product_id":"kawasaki-70z-ii-70z-iii-70z-iv-cylinder-head-workhorse","title":"Kawasaki 70Z-II, 70Z-III \u0026 70Z-IV Cylinder Head Reman - Workhorse (5.9L 12V)","description":"\u003cp\u003eKeep your heavy equipment operational under the most demanding workloads. The Workhorse tier cylinder head for the Kawasaki 70Z-II, 70Z-III, and 70Z-IV wheel loader (Cummins 5.9L 12-valve engine) is specifically engineered for sustained heavy-duty industrial work, continuous duty cycles, and extreme thermal loads. Assembled using a renewed, pressure-tested OEM core combined with brand-new, high-quality internal components, this cylinder head integrates premium durability upgrades to handle elevated cylinder pressures and eliminate common field failures.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch3\u003eUpgrades Over the Daily Driver: Precision O-Rings\u003c\/h3\u003e\n\u003cp\u003eSevere industrial operation causes rapid thermal expansion, which is the leading cause of head gasket failure in heavy equipment. The Workhorse model solves this by features precision-cut O-rings machined directly into the deck surface. This mechanical modification locks the head gasket securely in place, dramatically improving sealing under high cylinder pressures and severe operating temperatures to ensure zero combustion leaks.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch3\u003ePremium Component Breakdown\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eRemanufactured Casting:\u003c\/b\u003e Built from a high-quality OEM core casting that has passed rigorous magnetic testing and is machined to like-new specifications.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eNew Valves:\u003c\/b\u003e Equipped with new, high-quality intake and exhaust valves, inspected for proper seating, depth, and clearance.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eNew Valve Springs and Retainers:\u003c\/b\u003e Utilizes brand-new valve springs matched to the rigorous requirements of industrial engines, with durable retainers and locks for secure operation during prolonged high-torque output.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eNew Injector Cups:\u003c\/b\u003e Pre-installed new injector cups ensure an absolute fuel seal and prevent coolant contamination.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch3\u003eKey Features and Heavy-Duty Fixes\u003c\/h3\u003e\n\u003cp\u003eThis head features critical performance and structural upgrades, backed by an intense inspection protocol to guarantee every industrial specification is met.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003e40 PSI Pressure Testing:\u003c\/b\u003e After machining, every cylinder head is pressure-tested at 40 PSI to confirm zero leaks and ensure casting integrity.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eBlow-Proof Plugs:\u003c\/b\u003e Threaded, blow-proof plugs are installed in the top of the head for increased security and leak prevention, replacing factory pressed-in plugs that fail under thermal stress.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eFinal Quality Control:\u003c\/b\u003e The head undergoes an extensive final cleaning and strict quality control inspection. A detailed sign-off sheet is generated, measuring and recording critical specifications using a profilometer, including:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003eValve Recessions\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eStem Heights\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eInstalled Spring Heights\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eSpring Pressures\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eKeeper and Lock Positions\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eRoughness Average (RA) Finish\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch3\u003ePrecision Machining Process\u003c\/h3\u003e\n\u003cp\u003eChoate Engineering Performance has incorporated critical modifications to address common factory vulnerabilities of the 5.9L Cummins industrial cylinder heads, drastically improving field reliability:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eOptimal Sealing Surface:\u003c\/b\u003e The deck is resurfaced to meet or exceed OEM specifications for Roughness Average (Ra), maximizing the sealing surface performance for the head gasket.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eValve Train Geometry Alteration:\u003c\/b\u003e The head is custom blueprinted to alter valve height and valve recession, achieving maximum reliability under continuous loads.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eLifter Longevity Fix:\u003c\/b\u003e Valve stem heights are precisely altered to optimize valvetrain geometry and remove excessive preload. This crucial modification decreases wear and significantly extends the life of the lifters and camshaft.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eOptimized Flow and Sealing:\u003c\/b\u003e Valve seats are cut with a precise three-angle profile to optimize efficiency and ensure an airtight seal.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eValve Prep:\u003c\/b\u003e Valves are reground and margins are meticulously inspected to guarantee proper sealing against the new seats.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eAll-New Wear Components:\u003c\/b\u003e New valve stem seals, valve seats, valve guides, and injector cups are installed across the board.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch3\u003eMeticulous Cleaning and Prep Process\u003c\/h3\u003e\n\u003cp\u003eOur commitment to quality begins before machining, with an intensive cleaning and stress-relieving process to ensure a flawless starting point:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eMagnetic Particle Inspection (MPI):\u003c\/b\u003e Each core is subjected to MPI testing to thoroughly check for any cracks or subsurface imperfections.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eThermal Stress Relieving:\u003c\/b\u003e The head undergoes a stress-relieving process in a specialized furnace to eliminate residual industrial oils and grease by turning them into ash.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eMaterial Relaxation:\u003c\/b\u003e The head is shot-blasted to remove rust and scaling. This crucial step relaxes the cast iron material before precision machining begins.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eThread Prep:\u003c\/b\u003e All broken bolts and studs are professionally removed to ensure threads are clean, chased, and ready for a seamless installation.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Choate Performance","offers":[{"title":"Default Title","offer_id":67304116355376,"sku":"CEP59KA12VWHR","price":1899.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0941\/2680\/1200\/files\/5.9Cummins12vWorkhorseCylinderHead_2.png?v=1783557951","url":"https:\/\/choateperformance.com\/products\/kawasaki-70z-ii-70z-iii-70z-iv-cylinder-head-workhorse","provider":"choateperformance","version":"1.0","type":"link"}